312140721 has 32 divisors (see below), whose sum is σ = 449971200. Its totient is φ = 191868480.

The previous prime is 312140713. The next prime is 312140743. The reversal of 312140721 is 127041213.

It is not a de Polignac number, because 312140721 - 2³ = 312140713 is a prime.

It is not an unprimeable number, because it can be changed into a prime (312147721) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 371620 + ... + 372458.

It is an arithmetic number, because the mean of its divisors is an integer number (14061600).

Almost surely, 2^312140721 is an apocalyptic number.

It is an amenable number.

312140721 is a deficient number, since it is larger than the sum of its proper divisors (137830479).

312140721 is a wasteful number, since it uses less digits than its factorization.

312140721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1029.

The product of its (nonzero) digits is 336, while the sum is 21.

The square root of 312140721 is about 17667.5046625153. The cubic root of 312140721 is about 678.3442422220.

Adding to 312140721 its reverse (127041213), we get a palindrome (439181934).

The spelling of 312140721 in words is "three hundred twelve million, one hundred forty thousand, seven hundred twenty-one".